<html><head><title> EiC's Bug Report List</title></head>
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	EiC's Bug list 

Template bug report form
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REPORTER:
PLATFORM:
PROBLEM:
EXAMPLE:
POSSIBLE SOLUTION:
TESTPROGRAM:
STATUS: Not Fixed

----------------------------------------------
REPORTER: Martin Gonda (9/1/96)
PROBLEM:
	Possibly fix up pre-processor, so that illegal
	statements which start with a hash (#) are caught.
EXAMPLE:
	#hello     ...would get through without an error
POSSIBLE SOLUTION:
TESTPROGAM:
STATUS:	Fixed by Ed Breen
----------------------------------------------
REPORTER: Ed Breen
PROBLEM: 
	A failure to correctly process:

	EiC > for(i=0;i<3;i++) { int a[5]; }

EXAMPLE:

   EiC 9> for(i=0;i<3;i++) { int a[5]; }

   0:checkar  2 0          10:rvalint  5 0        
   1:pushint  20           11:incint   1          
   2:massign  12 1         12:stoint   5 0        
   3:pushint  0            13:decint   1          
   4:stoint   5 0          14:rvalint  5 0        
   5:jmpU     7            15:bump     1          
   6:rvalptr  1 1          16:pushint  3          
   7:stoptr   0 1          17:ltint               
   8:fmem     1 1          18:jmpTint  3          
   9:reducear 2            19:halt                

POSSIBLE SOLUTION:

	The free memory instruction and the reducear instruction,
lines 8 and 9, have been inserted too early. The resulting bytecode
sequence should be more like:

   EiC 11> {for(i=0;i<3;i++) { int a[5]; }}

   0:checkar  2 0          10:stoint   5 0        
   1:pushint  20           11:decint   1          
   2:massign  1 1          12:rvalint  5 0        
   3:pushint  0            13:bump     1          
   4:stoint   5 0          14:pushint  3          
   5:jmpU     12           15:ltint               
   6:rvalptr  1 1          16:jmpTint  6          
   7:stoptr   0 1          17:fmem     1 1        
   8:rvalint  5 0          18:reducear 2          
   9:incint   1            19:halt                

The above solution forces an extra scoping level. However, this is not
sensible for every translation unit entered at the command line.  But
maybe, EiC could keep track of the level of statement nesting
also. Then it could addinlocals (parser.c) at the end of each zero
level statement, in addition to the current method of when the scoping
level drops back to file scope?

	if(S_LEVEL == 1 && Stmts == 0) 
		addinlocals(...);

TESTPROGRAM: see example
STATUS: Fixed, as outlined in possible solution.
----------------------------------------------
REPORTER: Ed Breen
PROBLEM:
	Correct the get float/double section in the _Uscanf
EXAMPLE:
	for ungetting characters, for example,
		fmt string = %f %s 
		input = 100ergs. 
		output = 100 rgs
		output should be 100 ergs.
POSSIBLE SOLUTION:
	Solution requires 2 ungets not just 1.
TESTPROGRAM:
	errScanf1.c
STATUS: Fixed by Ed Breen.
----------------------------------------------
REPORTER: Ed Breen
PROBLEM:
	Correct the problem with builtin functions
	being prototyped when an error occurs. This problem
	means that the user will have to restart EiC
	to recover properly. 
EXAMPLE:
POSSIBLE SOLUTION:
	It Has to do with the error recover stategy implemented when
	the signals were added to EiC.
TESTPOGRAM:  	
STATUS: Fixed (hopefully)
----------------------------------------------
REPORTER: Ed Breen
PROBLEM:  Does not allow redeclaration of structure specifiers:
EXAMPLE:
	struct Dvector { double x, y; };
	struct Dvector { double x, y; };

Error in tptr2.c near line 6: Illegal use of struct/union
Error in tptr2.c near line 8: Expected  ; 

POSSIBLE SOLUTION: ?
TESTPROGRAM: see  example
STATUS: Fixed by Ed Breen
----------------------------------------------
REPORTER: Ed Breen
PROBLEM:  Memory leak caused when redefining an array:
EXAMPLE:
	int a[5];
	int a[5];	
item 1865 Create line 264 file cdecl.c nbytes 20

POSSIBLE SOLUTION:  look at freetype.
TESTPROGRAM: see example
STATUS: Fixed, added routine freeArray to cdecl.c
----------------------------------------------
REPORTER: Ed Breen
PROBLEM:  Memory leak caused by exit();
EXAMPLE:
	see file t1.c; this directory
	#include t1.c
	:memdump
        (void)
item 4436 Create line 127 file interpre.c nbytes 1200
item 4435 Create line 41 file typemod.c nbytes 16

POSSIBLE SOLUTION:
TESTPROGRAM: see example
STATUS: Not Fixed
----------------------------------------------
REPORTER:  Ed Breen
PROBLEM:   False diagnostic
EXAMPLE:
	EiC 5> if (sizeof (char) * 8 == sizeof (double));
	Warning: in ::EiC:: near line 5:  Non relational operation
	0:pushint  1          
	1:jmpFint  2          
   	2:halt                

POSSIBLE SOLUTION: Because sizeof (char) * 8 == sizeof (double) 
		resolves to a constant and this might be causing the
		problem.
TESTPROGRAM: see example
STATUS: Fixed, corrected bug with unsigned 
           constant binary relational operators not
	  converting the result to int properly.
----------------------------------------------
REPORTER: Ed Breen
PROBLEM:  Parses an incorrect declaration
EXAMPLE:
	EiC 1> int (* foo[10])()[];
        	(void)
	EiC 2> :show foo
	foo -> ARY[10]* dec_Func (void ) returning ARY[0]int 
        	(void)
	... // Simplification of the problem

	EiC 10> int foo()[];
        	(void)
	EiC 11> :show foo
	foo -> dec_Func (void ) returning ARY[0]int 
        	(void)


POSSIBLE SOLUTION: Check function declaration
	code.
TESTPROGRAM: see example
STATUS: Fixed, added the check_decl function in
	the decl.c module. Not an optimal solution,
	but it catches both the above errors and
	more.
----------------------------------------------
REPORTER: Ed Breen
PROBLEM: False Ambiguous re-declaration
EXAMPLE: 
let t.c contain the following two lines 

typedef struct { int a, b; } ab_t;
ab_t * func(void) { ab_t * p; return p; }

	EiC session

EiC 2> #include t.c
        (void)
EiC 3> :rm ab_t
        (void)
EiC 4> #include t.c
Error in t.c near line 30: Ambiguous re-declaration of `func'

POSSIBLE SOLUTION:

	This has something to do with the memory being freed --
	I could make it illegal to remove the last
	occurrence of a structure. But that would make
	it impossible to change an existing structure. Better
	still, handle memory aliasing in a more creative
	way -- a big job, but probably worth it. 

TESTPROGRAM:
	see above.

STATUS: Fixed by Ed Breen -- it turned out to be
quite simple. 

----------------------------------------------
REPORTER: Ed Breen
PROBLEM: EiC does not cast structures properly using va_args.
EXAMPLE:

typedef struct { int a, b; } ab_t;
ab_t a = {5,5};

int p(char *fmt, ...)
{
    ab_t x;
    va_list ap;    
    va_start(ap, fmt);
    
    x = va_arg(ap, ab_t);
    va_end(ap);

    return x.a;
}

// the following call returns garbage!

p("",a);


POSSIBLE SOLUTION:

	The solution is to get the stack code to `drefptr' the pointer
contained at the `ap' stack position, immediately before the `refmem'
instruction. Although, this is easy to do, it upsets other existing
code such as referencing members within an array of structures and
structure assignments -- a rethink is in order.


TESTPROGRAM:
	see above

STATUS: Not Fixed, but the current EiC implementation
	flags the passing of a structure or union to
	a variadic function as an error.
----------------------------------------------

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